Shell floats plan for offshore carbon capture

Australian
Tuesday 22/4/2008 Page: 25

ROYAL Dutch Shell is considering capturing and burying carbon dioxide at its planned Prelude floating liquefied natural gas operation off the coast of Western Australia, according to documents lodged with environmental regulators. Shell is looking to build a 3.5 million tonnes a year floating LNG plant to process gas from the Prelude field, about 450km northeast of Broome, according to an application lodged with the federal Environment Department earlier this month.

The project has "potential for carbon dioxide sequestration, thereby reducing the carbon footprint of the project", Shell says in the application. Floating LNG, in which gas is liquefied offshore on a floating plant rather than piping the fuel to shore, is an untested technology that large oil companies, including Shell, are trying to commercialise as LNG plant development costs spiral higher and as LNG prices make developing isolated gas fields more attractive.

The move to sequester, or capture and store underground, the carbon dioxide from the gas comes as the federal Government plans to bring in a carbon trading scheme by 2010 as part of a plan to limit greenhouse gas emissions. "A successful Prelude floating LNG development will provide the catalyst for the development of other stranded gas fields in Australia and elsewhere," Shell says in the application. Shell, along with partner Woodside Petroleum, is considering using floating LNG at the Sunrise project in the Timor Sea.

The floating LNG plant is expected to be 480m long with a width of between 70m and 80m and would be built outside Australia and towed to Prelude, Shell says. The plant is expected to run for 25 years to 2037, Shell says, indicating an expected start date of 2012. The planned unit, which would be anchored to the seabed, would not disconnect in bad weather and would be designed to survive a one in 10,000 years cyclone. Shell executive director of gas and power Linda Cook said earlier this month that an application had been lodged. She said preliminary estimates showed the Prelude field held between 2 trillion and 3 trillion cubic feet of gas.